13.1 Adjustment and forfeiture of surface water allocation

Supporting information

This line item refers to the the total adjustment made on surface water allocations for other lumped holders, industrial, and commercial holders and stock and domestic holders for the 2012–13 year.

The volume recognised in the water accounting statements of 122,416 ML represents the adjustment made by the National Water Account to reconcile the water accounting statements, it does not represent an actual forfeiture of the licensed allocation by individual license holders at the end of the water year on 30 June.

Quantification approach

Data source

Water Sharing Plan for the Greater Metropolitan Unregulated River Water Sources; entitlement and diversion data recorded in databases and water management licences.

Provided by

The Bureau calculated opening and closing balance; New South Wales Office of Water provided entitlement and diversion data.


Under the water sharing plan, carry-over of any unused allocation at the end of the year is allowed for licences issued to other lumped holders, and stock and domestic holders. The maximum volume of carry-over allowed is determined by the rules in the water sharing plan and the volume of water diverted under the licence. As the volume of water diverted under these licences is an estimate (refer to line item 17.11 Entitled diversion of allocated surface water to users), the carry-over volume could not be quantified. Therefore, for the purposes of the National Water Account, the carry-over volume (opening and closing balance as reported in 5.1 Surface water allocation remaining) was assumed to be zero.

In order to the balance the account, the liability decrease reported in this line item is equal to any remaining unused allocation.

Calculation methods for the announced allocation and measured diversions are available in:

Assumptions, limitations, caveats and approximations

  • Carry-over has not been quantified.
  • Diversions made under the category of stock and domestic or other lumped holder have been estimated.
  • Liability decrease is assumed to be equal to the remaining unused allocation at 30 June.

Uncertainty information

For entitlements: the allocation/claim was derived from the Water Sharing Plan for the Greater Metropolitan Unregulated River Water Sources. Uncertainty was not quantified.

For diversions: estimated uncertainty is +/– 30% to 50% based on professional judgement and established practice within the New South Wales Office of Water.

Comparative year

Due to the updates reported in 21.1 Surface water allocation announcements the value reported in the 2011–12 year has been restated from 125,455 ML to 254,054 ML.